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改性活性炭的粒级对吸附金-硫代硫酸根络离子的影响研究 被引量:1
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作者 余洪 宋文强 +2 位作者 程彦玲 张汉泉 谢蕾 《中国矿业》 2023年第1期141-149,共9页
硫代硫酸盐提金法是最有望取代氰化法的无毒提金方法,但浸出液中金-硫代硫酸根络离子Au(S_(2)O_(3))_(2)^(3-)无法经济有效地回收阻碍了该方法的工业应用。为了提高活性炭对Au(S_(2)O_(3))_(2)^(3-)的负载量,本文以三种粒级的活性炭为原... 硫代硫酸盐提金法是最有望取代氰化法的无毒提金方法,但浸出液中金-硫代硫酸根络离子Au(S_(2)O_(3))_(2)^(3-)无法经济有效地回收阻碍了该方法的工业应用。为了提高活性炭对Au(S_(2)O_(3))_(2)^(3-)的负载量,本文以三种粒级的活性炭为原料,采用三聚氰胺浸渍-高温热活化法制备了改性活性炭。通过静态吸附法、孔径与比表面积分析仪、SEM-EDS和XPS等方法详细研究了三聚氰胺用量、浸渍温度、热活化温度和时间等对改性活性炭吸附Au(S_(2)O_(3))_(2)^(3-)的影响和吸附机理。研究结果表明,粒级为0.45~0.90 mm的活性炭添加3.75%的三聚氰胺,50℃下浸渍改性后,在温度为750℃下热活化60 min,制备的活性炭对Au(S_(2)O_(3))_(2)^(3-)的负载量最大,为553.35μg/g。吸附机理研究发现,粒级为0.45~0.90 mm的活性炭改性后,具有较大的微孔占比和适宜的平均孔径;季氮官能团增加了活性炭表面的正电性,含氧官能团提升了活性炭的亲水性,这些因素共同作用极大提升了改性活性炭对Au(S_(2)O_(3))_(2)^(3-)的吸附能力。 展开更多
关键词 活性炭 改性 粒级 吸附 金-硫酸根络离子
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氮掺杂活性炭的制备及其吸附金-硫代硫酸根配离子的动力学研究
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作者 谢蕾 张汉泉 +1 位作者 路漫漫 余洪 《湿法冶金》 CAS 北大核心 2023年第4期400-407,共8页
针对浸出液中金-硫代硫酸根配离子(Au(S_(2)O_(3))_(2)^(3-))难以被活性炭吸附问题,研究了以椰壳活性炭为原料,三聚氰胺为氮源,采用热活化氮掺杂法制备改性活性炭(AC-N)。考察了浸出液初始pH、吸附时间、吸附温度、初始金质量浓度、Na_(... 针对浸出液中金-硫代硫酸根配离子(Au(S_(2)O_(3))_(2)^(3-))难以被活性炭吸附问题,研究了以椰壳活性炭为原料,三聚氰胺为氮源,采用热活化氮掺杂法制备改性活性炭(AC-N)。考察了浸出液初始pH、吸附时间、吸附温度、初始金质量浓度、Na_(2)S_(2)O_(3)浓度、S_(4)O_(6)^(2-)浓度和主要金属离子对AC-N吸附Au(S_(2)O_(3))_(2)^(3-)的影响。结果表明:AC-N对Au(S_(2)O_(3))_(2)^(3-)吸附量随pH和温度升高呈先升高后下降趋势,随初始金质量浓度增大呈先升高后降低又升高趋势,在初始金质量浓度为20 mg/L条件下,Au(S_(2)O_(3))_(2)^(3-)吸附量达最大;Na_(2)S_(2)O_(3)易氧化分解,其产物S_(4)O_(6)^(2-)对金有钝化作用,Na_(2)S_(2)O_(3)浓度增大会抑制AC-N对Au(S_(2)O_(3))_(2)^(3-)的吸附;随共存金属离子Cu^(2+)、Pb^(2+)和Zn^(2+)质量浓度增大,Au(S_(2)O_(3))_(2)^(3-)吸附量呈先升高后下降趋势,有NH_(3)存在时,NH_(3)可与Cu^(2+)形成Cu(NH_(3))_(4)^(2+),减少Na_(2)S_(2)O_(3)消耗。吸附动力学结果表明,AC-N对Au(S_(2)O_(3))_(2)^(3-)的吸附速率先快后慢,30 h后吸附达饱和状态,吸附过程符合准一级动力学模型,吸附速率受表面液膜扩散和颗粒内扩散共同控制。 展开更多
关键词 吸附 活性炭 改性 金-硫酸根配离子 动力学
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安徽铜官山铜-铁-金-硫矿床的地球化学特征 被引量:14
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作者 李红阳 李英杰 +4 位作者 康桂玲 曹积飞 杨竹森 侯增谦 蒙义峰 《地质科学》 CAS CSCD 北大核心 2008年第2期370-376,共7页
铜官山铜-铁-金-硫矿床发育上部层状矿体和下部网脉状矿体,地球化学特征呈现出明显的垂向变化和二元结构性。从下部网脉状矿化岩石到上部层状矿石,CaO、MgO、Fe2O3、FeO等含量和δ18O值总体逐渐增高,SiO2、Al2O3、TiO2、K2O、Na2O、REE... 铜官山铜-铁-金-硫矿床发育上部层状矿体和下部网脉状矿体,地球化学特征呈现出明显的垂向变化和二元结构性。从下部网脉状矿化岩石到上部层状矿石,CaO、MgO、Fe2O3、FeO等含量和δ18O值总体逐渐增高,SiO2、Al2O3、TiO2、K2O、Na2O、REE等含量和流体包裹体温度(341.9℃→178.0℃)及δ34S值总体逐渐降低。黄铁矿δ34S值为(+2.1^+7.9)‰,上部层状块状矿石中方解石和石英δ18O平均值为+13.9‰,下部网脉状矿化岩(矿)石中脉石英或全岩δ18O平均值为+11.7‰。 展开更多
关键词 --金-硫矿床 二元结构 地球化学 安徽铜官山
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金-硫团簇负离子组成特征的探讨 被引量:4
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作者 梁汉东 刘敦一 《物理化学学报》 SCIE CAS CSCD 北大核心 2001年第9期859-864,共6页
报导了金 /硫靶在静态二次离子质谱实验条件下形成的组成通式为 Au1- 15S0- 5的团簇负离子 .其中 ,Aun组成系列具有典型的奇数优势 ,属于金的一元团簇负离子 .其余组成系列( Au1- 15S1- 5)则属于金-硫二元团簇负离子 .研究发现 ,... 报导了金 /硫靶在静态二次离子质谱实验条件下形成的组成通式为 Au1- 15S0- 5的团簇负离子 .其中 ,Aun组成系列具有典型的奇数优势 ,属于金的一元团簇负离子 .其余组成系列( Au1- 15S1- 5)则属于金-硫二元团簇负离子 .研究发现 ,金-硫团簇负离子具有以下与组成密切相关的特征 :( 1)它们继承了金一元团簇负离子的奇数优势 ;( 2)它们中硫原子数仅限于 5,而金原子数则在较大范围变化 ;( 3)它们完全没有多数其它金属与非金属(包括硫)二元团簇正 /负离子共有的 MenNn型组成优势 ;( 4)它们以上组成特征及其它细节恰似碳-磷这样的典型非金属二元团簇正 /负离子 .基于这样的组成特征可提出 ,金-硫团簇负离子在构成上包含着相对完整的金一元团簇组件 ,在形成机制上源于金一元团簇与硫一元团簇(或称为 :限于五原子的多硫单元)之间的再团簇化 .关于再团簇化机制中的相互作用问题 ,即两类团簇间是依靠末端原子交叉成键还是依赖两类团簇中异种原子之间静电诱导力等"非共价键"作用的问题 ,则有待于今后研究证实 . 展开更多
关键词 金-硫团簇 再团簇化 团簇负离子 组成特征 团簇化机制 静态二次离子质谱
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氧化-热活化氮掺杂改性活性炭吸附金-硫代硫酸根络离子 被引量:1
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作者 张汉泉 谢蕾 +3 位作者 张鹏飞 邢张溪 胡敏 余洪 《应用化工》 CAS CSCD 北大核心 2021年第4期985-990,996,共7页
硫代硫酸盐法是最有可能取代氰化法的浸金方法,但活性炭不能有效吸附Au(S_(2)O_(3))^(2-)_(2),使得硫代硫酸盐浸金法难以得到工业应用。为提高活性炭对Au(S_(2)O_(3))^(2-)_(2)的吸附效果,采用氧化-热活化氮掺杂法对活性炭改性,H_(2)O_... 硫代硫酸盐法是最有可能取代氰化法的浸金方法,但活性炭不能有效吸附Au(S_(2)O_(3))^(2-)_(2),使得硫代硫酸盐浸金法难以得到工业应用。为提高活性炭对Au(S_(2)O_(3))^(2-)_(2)的吸附效果,采用氧化-热活化氮掺杂法对活性炭改性,H_(2)O_(2)为氧化剂,三聚氰胺与氨水为氮源,热活化制备出不同的氮掺杂活性炭。采用Boehm滴定法和X射线光电子能谱(XPS)分析了活性炭表面含氧酸官能团含量、元素含量及官能团种类。结果表明,氧化活性炭过程中,在H_(2)O_(2)的浓度为4 mol/L,温度为55℃下改性1 h,活性炭表面酸性官能团含量为0.70574 mmol/g。在热活化氮掺杂过程中,三聚氰胺的掺杂效果高于氨水,三聚氰胺用量为0.016 mol/L,室温掺杂4 h,且在900℃下热活化2 h所得的活性炭对Au(S_(2)O_(3))^(2-)_(2)的最大吸附量为547.12μg/g,热活化氮掺杂活性炭表面负载吡咯氮显著提升了其对Au(S_(2)O_(3))^(2-)_(2)的负载量。 展开更多
关键词 活性炭 改性 氧化 热活化-氮掺杂 吸附 金-硫酸根络离子
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安徽水竹岭铜-铁-金-硫矿床同位素地球化学特征
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作者 李红阳 冯景志 +4 位作者 王金芳 侯增谦 杨竹森 王聪颖 陈文韬 《地质与勘探》 CAS CSCD 北大核心 2010年第1期70-75,共6页
水竹岭铜-铁-金-硫矿床发育上部层状矿体和下部脉状矿体。上部层状矿石重晶石δ34S值为+19.9‰。上部层状矿石黄铁矿δ34S值为+0.9~+5.8‰,下部脉状矿石黄铁矿δ34S值为+3.2~+6.4‰。下部脉状矿体中方解石的δ18O值为+13.3‰,δ13C值... 水竹岭铜-铁-金-硫矿床发育上部层状矿体和下部脉状矿体。上部层状矿石重晶石δ34S值为+19.9‰。上部层状矿石黄铁矿δ34S值为+0.9~+5.8‰,下部脉状矿石黄铁矿δ34S值为+3.2~+6.4‰。下部脉状矿体中方解石的δ18O值为+13.3‰,δ13C值为1.2‰,上部层状矿石白云石的δ18O值为+14.1‰,δ13C值为2.2‰。下部脉状矿石和矿化岩石中黄铁矿的206Pb/204Pb、207Pb/204Pb、208Pb/204Pb平均值分别为18.2241、15.5245和38.2289;上部层状矿石中黄铁矿的206Pb/204Pb、207Pb/204Pb、208Pb/204Pb平均值分别为18.0692、15.5020和38.1232。从下部脉状矿石到上部层状矿石,黄铁矿的δ34S值、206Pb/204Pb、207Pb/204Pb、208Pb/204Pb平均值逐渐降低,δ18O值和δ13C值等逐渐增高。地质和同位素地球化学特征反映水竹岭铜-铁-金-硫矿床为海底热水喷流沉积成因,揭示了块状硫化物矿床的二元结构性。 展开更多
关键词 --金-硫矿床二元结构 同位素地球化学安徽水竹岭
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ZNT1 Involves Cuproptosis through Regulating MTF1-conduced Expression of MT1X under Copper Overload
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作者 Wu Yue Yang Tingyun +4 位作者 Yan Bo Ai Youwei Chen Fang Ma Juan Liu Sijin 《生态毒理学报》 CAS CSCD 北大核心 2024年第4期53-70,共18页
Industrial activities such as smelting emissions,mineral combustion and industrial wastewater discharge might lead to copper pollution in the environment.This kind of copper pollution has harmful effects on aquatic o ... Industrial activities such as smelting emissions,mineral combustion and industrial wastewater discharge might lead to copper pollution in the environment.This kind of copper pollution has harmful effects on aquatic o rganisms,plants and animals through direct or indirect exposure.However,the current understanding of the toxicity of copper is rather limited.Copper overload can perturb intracellular homeostasis and induce oxidative stress and e ven cell death.Recently,cuproptosis has been identified as a copper-dependent form of cell death induced by o xidative stress in mitochondria.We uncover here that zinc transporter 1(ZNT1)is an important regulator involved in cuproptosis.Firstly,we established the copper overload-induced cell death model with the overexpression of copper importer SLC31A1 in HeLa cells.Using this model,we conducted unbiased genome-wide CRISPR-Cas9 screens in cells treated with copper.Our results revealed a significant enrichment of ZNT1 gene in both library A and library B plasmids.Knocking out of ZNT1 in HeLa cells notably prevented cuproptosis.Subsequent knockout of metal transcription factor 1(MTF1)in ZNT1-deficient cells nearly abolished their ability to resist copper-induced cell death.However,overexpression of metallothionein 1X(MT1X)in the double-knockout cells could p artially restored the resistance to cuproptosis by loss of MTF1.Mechanistically,knockout of ZNT1 could promote MT1X expression by activating MTF1.As a consequence,the interaction between MT1X and copper was e nhanced,reducing the flow of copper into mitochondria and eliminating mitochondria damage.Taken together,this study reveals the important role of ZNT1 in cuproptosis and shows MTF1-MT1X axis mediated resistance to c uproptosis.Moreover,our study will help to understand the regulatory mechanism of cellular and systemic copper homeostasis under copper overload,and present insights into novel treatments for damages caused by both genetic copper overload diseases and environmental copper contamination. 展开更多
关键词 COPPER cuproptosis ZNT1 MT1X
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安徽峙门口铜—铁—金—硫矿床地球化学特征
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作者 李红阳 王金芳 +5 位作者 冯景志 侯增谦 杨竹森 蒙义峰 王聪颖 陈文韬 《地质科学》 CAS CSCD 北大核心 2010年第3期863-872,共10页
峙门口铜—铁—金—硫矿床发育上部层状矿体和下部脉状矿体。上部层状矿石重晶石的δ^(34)S值为+14.10‰~+18.90‰。上部层状矿石黄铁矿和方铅矿的δ^(34)S值为+3.50‰~+5.84‰,下部脉状矿石黄铁矿的δ^(34)S值为+4.80‰~+6.80‰。... 峙门口铜—铁—金—硫矿床发育上部层状矿体和下部脉状矿体。上部层状矿石重晶石的δ^(34)S值为+14.10‰~+18.90‰。上部层状矿石黄铁矿和方铅矿的δ^(34)S值为+3.50‰~+5.84‰,下部脉状矿石黄铁矿的δ^(34)S值为+4.80‰~+6.80‰。下部脉状矿石中脉石英的δ^(18)O值为+14.3‰~+1 8.5‰,δ^(30)Si值为-0.3%0~-0.2‰。下部脉状矿石黄铁矿Re/Os比值为78.342~175.540,上(顶)部层状矿石中黄铁矿Re/Os比值为62.298~169.545。从下部脉状矿石到上部层状矿石,δ^(34)S值、Re/Os比值和流体包裹体温度249 ℃→97 ℃逐渐降低,^(206)Pb/^(204)Pb、^(207)Pb/^(204)Pb、^(208)Pb/^(204)Pb平均值和Os_总、Re、^(187)Re等含量逐渐增高。矿石黄铁矿Re-Os同位素等时线年龄303±33 Ma。地质地球化学特征反映峙门口铜—铁—金—硫矿床为海底热水喷流沉积成因。 展开更多
关键词 --金-硫矿床 二元结构 地球化学 安徽峙门口
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家兔肝脏中锌—金硫蛋白提取工艺的研究 被引量:5
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作者 吴萍 彭新君 +3 位作者 何斌 赵碧清 杨方明 尤昭玲 《湖南中医学院学报》 2004年第3期48-51,共4页
目的研究硫酸锌诱导的家兔肝脏锌 -金属硫蛋白 (Zn—MT)的提取工艺。方法选用正交试验法对硫酸锌诱导的兔肝锌 -金属硫蛋白的提取工艺进行优选 ,以原子吸收法测得锌提取量和紫外分光光度法测得巯基活性及杂蛋白浓度为评价指标 ,选用L9( ... 目的研究硫酸锌诱导的家兔肝脏锌 -金属硫蛋白 (Zn—MT)的提取工艺。方法选用正交试验法对硫酸锌诱导的兔肝锌 -金属硫蛋白的提取工艺进行优选 ,以原子吸收法测得锌提取量和紫外分光光度法测得巯基活性及杂蛋白浓度为评价指标 ,选用L9( 3 4 )正交表进行正交实验。考察影响提取锌—金属硫蛋白的 4个因素分别为 :pH8.6的Tris—HCl缓冲溶液和乙醇—氯仿 ( 1 .0 3∶0 .0 8)溶液作为提取剂的用量、80℃水浴变性时间、超声强度及时间。并且对提取液用SephadexG— 5 0凝胶柱色谱法分离纯化了Zn—MT ,考察提取工艺对其分离纯化效果的影响。结果最佳方案为 :每克兔肝用 3mL缓冲溶液和 2mL乙醇—氯仿溶液 ,80℃水浴变性 6min,中等超声强度提取 2 0min。凝胶柱色谱法纯化得到Zn—MT粗品产率约为 2 .5mg/g肝 ,而提取工艺中杂蛋白溶出量可影响Zn—MT的分离纯化效果。结论为常规实验室制备Zn—MT提供了简便可靠的方法。 展开更多
关键词 -蛋白 提取工艺 差示紫外分光光度法 原子吸收分光光度法
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Au_nS_m^-原子簇离子的激光产生及其质谱研究
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作者 周异男 周勇 王改平 《河南职业技术师范学院学报》 2000年第1期39-41,共3页
以高能量密度的脉冲激光束在高真空中溅射金粉与硫粉的混合物 ,产生了丰富的金 -硫二元原子簇负离子 Aun S- m( n=1~ 2 0 ,m=1~ 1 1 ) ,并记录了它们的飞行时间质谱 ;随着簇离子的逐渐增大 ,其组分子中硫的相对含量逐渐减少 ,对于成... 以高能量密度的脉冲激光束在高真空中溅射金粉与硫粉的混合物 ,产生了丰富的金 -硫二元原子簇负离子 Aun S- m( n=1~ 2 0 ,m=1~ 1 1 ) ,并记录了它们的飞行时间质谱 ;随着簇离子的逐渐增大 ,其组分子中硫的相对含量逐渐减少 ,对于成簇的金原子可能相互成键 ,构成簇离子的核心 ,所含金原子数 n相同的各簇离子大多符合统计分布曲线 。 展开更多
关键词 激光溅射 金-硫原子簇 飞行时间质谱 族离子
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Leaching of nickel-molybdenum sulfide ore in membrane biological reactor 被引量:1
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作者 陈家武 高从堦 +2 位作者 张启修 肖连生 张贵清 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第6期1395-1401,共7页
The bioleaching of molybdenum from its sulfide ore using a Mo-resistant thermophilic bacterium sulfolobus metallics combined with a membrane biological reactor(MBR) was studied.The experimental results showed that t... The bioleaching of molybdenum from its sulfide ore using a Mo-resistant thermophilic bacterium sulfolobus metallics combined with a membrane biological reactor(MBR) was studied.The experimental results showed that the concentration of Mo can be controlled by filter of the membrane in MBR and the toxicity of Mo to microorganism is decreased in the process of bioleaching.It was also evidenced that there were different leaching rates of Ni and Mo when the concentration of Mo was different.After leaching for 20 d in the MBR at Mo concentration of 395 mg/L,the leaching rates of Ni and Mo reached the maximum of 79.57% and 56.23% respectively under the conditions of 100 g/L of mineral density,65 ℃,pH=2 and 1.0 L/min of the aeration rate.While 75.59% Ni and 54.33% Mo were leached out in column without membrane under the same conditions. 展开更多
关键词 membrance biological reactor nickel-molybdenum sulfide ore sulfolobus metallics BIOLEACHING molybdenum toxicity
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紫外-可见-近红外光诱导自修复纳米复合水凝胶的制备及性能研究 被引量:3
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作者 燕宇 刘萍 +1 位作者 秦海利 刘欢欢 《现代化工》 CAS CSCD 北大核心 2020年第1期91-95,共5页
基于Au-S配位作用,将有机小分子BACA修饰在TiO2@Au纳米复合物表面并用作大交联剂,在反应单体、引发剂和催化剂存在下发生原位自由基聚合反应,制备了具有高强度的纳米复合水凝胶。探讨了纳米复合物交联剂对凝胶聚合物网络结构和机械性能... 基于Au-S配位作用,将有机小分子BACA修饰在TiO2@Au纳米复合物表面并用作大交联剂,在反应单体、引发剂和催化剂存在下发生原位自由基聚合反应,制备了具有高强度的纳米复合水凝胶。探讨了纳米复合物交联剂对凝胶聚合物网络结构和机械性能的影响。结果表明,纳米复合水凝胶显现出均匀、致密的聚合物网络,相对于普通有机小分子作交联剂,该凝胶的拉伸应变和断裂强度分别提高了2倍和21倍。该纳米复合水凝胶在紫外、可见以及近红外光下显现出高效、快速的自修复行为。 展开更多
关键词 金-硫 自修复 光诱导 纳米复合水凝胶 高强度
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Cloning and Expression Patterns of a Metallothionein-like GenehtMT2 of Helianthus tuberosus 被引量:3
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作者 常团结 陈蕾 +3 位作者 路子显 陈宛新 刘翔 朱祯 《Acta Botanica Sinica》 CSCD 2002年第10期1188-1188,共1页
A novel cDNA sequencehtMT2, which encodes a type 2 metallothionein_like protein, was isolated from Helianthus tuberosus L. tuber cDNA library. The whole sequence is 509 bp, including an open reading frame (ORF) of 240... A novel cDNA sequencehtMT2, which encodes a type 2 metallothionein_like protein, was isolated from Helianthus tuberosus L. tuber cDNA library. The whole sequence is 509 bp, including an open reading frame (ORF) of 240 bp, a 5′ UTR of 62 bp and a 3′ UTR of 207 bp. Two genomic sequences covering the coding region ofhtMT2were cloned by PCR reaction. Sequence analysis revealed that the genomic sequences htMTG_1 of 986 bp and htMTG_2 of 982 bp were both composed of three exons and two introns. The deduced protein consisted of 79 amino acid residues with a predicted molecular weight of 7.8 ku (kD). Amino_terminal and carboxy_terminal domains contained 8 and 7 cysteine residues respectively, separated by a central cysteine free spacer. Sequence alignment revealed that the predicted protein ofhtMT2 was homologous to type 2 metallothioneins (MTs) of plants. Southern blotting analysis indicated that htMT2was encoded by a small multi_gene family in H. tuberosus genome. Northern blotting analysis showed that htMT2 transcripts were detected in stems, leaves and leafstalks, but no transcripts were detected in roots. The expression level in stems was the highest among the above tissues. Transcripts in stems were significantly reduced by Cu 2+ treatment. Judging from the homologies between the deduced HtMT2 and other type 2 plant metallothioneins as well as responses to metal ions, we believe thatwere cloned by PCR reaction. Sequence analysis revealed that the genomic sequences htMTG_1 of 986 bp and htMTG_2 of 982 bp were both composed of three exons and two introns. The deduced protein consisted of 79 amino acid residues with a predicted molecular weight of 7.8 ku (kD). Amino_terminal and carboxy_terminal domains contained 8 and 7 cysteine residues respectively, separated by a central cysteine free spacer. Sequence alignment revealed that the predicted protein ofhtMT2 was homologous to type 2 metallothioneins (MTs) of plants. Southern blotting analysis indicated that htMT2was encoded by a small multi_gene family in H. tuberosus genome. Northern blotting analysis showed that htMT2 transcripts were detected in stems, leaves and leafstalks, but no transcripts were detected in roots. The expression level in stems was the highest among the above tissues. Transcripts in stems were significantly reduced by Cu 2+ treatment. Judging from the homologies between the deduced HtMT2 and other type 2 plant metallothioneins as well as responses to metal ions, we believe that[ShtMT2 encodes a new type 2 metallothionein. 展开更多
关键词 plant MT-like protein cDNA sequence gene expression metal ion treatment INTRON
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Classification and Nomenclature of Plant Metallothionein-like Proteins Based on Their Cysteine Arrangement Patterns 被引量:1
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作者 刘进元 吕暾 赵南明 《Acta Botanica Sinica》 CSCD 2000年第6期649-652,共4页
随着植物基因组研究的进展 ,在基因文库和蛋白文库登录的植物类金属硫蛋白基因已超过 5 0个 ,接近金属硫蛋白总数的 1/ 3,而且有不断上升的趋势。鉴于目前植物类金属硫蛋白命名与分类随意性太大 ,很有必要建立一个统一合理的命名与分类... 随着植物基因组研究的进展 ,在基因文库和蛋白文库登录的植物类金属硫蛋白基因已超过 5 0个 ,接近金属硫蛋白总数的 1/ 3,而且有不断上升的趋势。鉴于目前植物类金属硫蛋白命名与分类随意性太大 ,很有必要建立一个统一合理的命名与分类法。对植物类金属硫蛋白一级结构进行详细分析后 ,发现该蛋白两端富含半胱氨酸的区域内半胱氨酸的排列方式颇具规律性 ,进而提出了以半胱氨酸排列方式为基础的分类及命名法 ,并阐述了采用这种方法的理由及其可行性。 展开更多
关键词 plant metallothionein_like protein cysteine arrangement patterns CLASSIFICATION
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Modeling Rice rgMT as a Plant Metallothionein-Like Protein by the Distance Geometry and Homology Methods
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作者 吕暾 刘进元 +1 位作者 张日清 赵南明 《Acta Botanica Sinica》 CSCD 2003年第11期1297-1306,共10页
Rice metallothionein-like protein (rgMT) shows characteristics of a three-section pattern composed of two highly conserved cysteine rich (CR) domains in the terminals and a spacer without cysteine (cys) residues in th... Rice metallothionein-like protein (rgMT) shows characteristics of a three-section pattern composed of two highly conserved cysteine rich (CR) domains in the terminals and a spacer without cysteine (cys) residues in the center of the molecule. In this paper, the two CR domains and the spacer region were modeled by the distance geometry and homology methods separately. For the CR domains, twenty random models were generated for each cys combination based on the constraint conditions of CXC (C represents cys, X represents any amino acid other than cys), and CXXC motifs and a metal-sulfur chelating cluster. Four models for the N-terminal and two for C-terminal CR domain containing metal chelating structures formed by different combinations of cys were selected from 900 possible conformations. The GOR method was used to predict the secondary structure of the spacer region and its model was built by the homology method. After three parts of the protein were modeled, they were connected to form a three-dimensional structure model of rgMT. The whole conformation showed that rgMT could form two independent metal-sulfur chelating structures connected by a spacer peptide, without a structural or energy barrier for them to form two independent metal-chelating clusters just as mammalian metallothionein (MT) proteins. As all plant metallothionein-like (MT-L) proteins have the same primary structural characteristic, two CR domains connected by a spacer region, and many have the same cys arrangement pattern as rgMT, the three-dimensional structure model of rgMT will provide an important reference for the structural study of other plant MT-L proteins. 展开更多
关键词 distance geometry homology method rice metallothionein-like protein structural modeling
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Corrosion behaviour of die-cast AZ91D magnesium alloys in sodium sulphate solutions with different pH values 被引量:5
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作者 田赟 杨丽景 +4 位作者 李艳芳 卫英慧 侯利锋 李永刚 Ri-Ichi MURAKAMI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2011年第4期912-920,共9页
The corrosion behaviours of die-cast AZ91D magnesium alloys were investigated in 0.1 mol/L sodium sulphate (Na 2 SO 4 ) solutions with different pH values. The corrosion rates, morphologies, and compositions of the ... The corrosion behaviours of die-cast AZ91D magnesium alloys were investigated in 0.1 mol/L sodium sulphate (Na 2 SO 4 ) solutions with different pH values. The corrosion rates, morphologies, and compositions of the corrosion products were studied by means of scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), and X-ray diffractometry (XRD). The results indicate that the order of corrosion rates in Na 2 SO 4 solutions with various pH values is pH 2pH 4pH 7pH 9pH 12. The corrosion rates in acidic solutions are higher than those in alkaline solutions, and the corrosion products are mainly magnesium hydroxide (Mg(OH) 2 ) and hydrated sulphate pickeringite (MgAl 2 (SO 4 ) 4 ·22H 2 O). The results also indicate that the solution pH can influence the corrosion rate and morphology of corrosion products. Chloride ions and sulphate ions have different pitting initiation time. 展开更多
关键词 magnesium alloy CORROSION sodium sulphate pH value
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Modeling the Cysteine Rich Domain of Plant Metallothionein-like Protein 被引量:2
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作者 何红珍 朱春明 +3 位作者 吕暾 张日清 赵南明 刘进元 《Acta Botanica Sinica》 CSCD 2002年第10期1155-1159,共5页
With the progress of plant genome research, more than 50 plant metallothionein_like (MT_L) genes have been found, but only several MT_L proteins have been detected and no experimental structural information for MT_L p... With the progress of plant genome research, more than 50 plant metallothionein_like (MT_L) genes have been found, but only several MT_L proteins have been detected and no experimental structural information for MT_L proteins has been reported so far. Since detailed knowledge of the protein tertiary structure is required to understand its biological function, a method is needed to determine the structure of these proteins. In this study, the structural data of known mammal MT was used to determine the interatomic distance constraints of the CXC and CXXC motifs and the metal_sulfur chelating cluster. Then several possible MT conformations were predicted using a distance geometry algorithm. The statistical analysis was used to select those with much lower target function values and lower conformation energies as the predicted tertiary structural models of the cysteine_rich (CR) domains of these proteins. A suitable prediction method for modeling the CR domain of the plant MT_L protein was constructed. The accurately predicted result for the known structure of an MT protein from blue crab suggests that this method is practicable. The tertiary structures of CR domains of rape MT_L protein LSC54 was then modeled with this method. 展开更多
关键词 plant metallothionein-like protein cysteine rich domain tertiary structure prediction distance geometry algorithm
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Sulfide mineral bioleaching:Understanding of microbe-chemistry assisted hydrometallurgy technology and acid mine drainage environment protection 被引量:5
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作者 LIAO Rui YU Shi-chao +10 位作者 WU Bai-qiang ZHAO Chun-xiao LIN Hao HONG Mao-xin WU Hai-yan YANG Cong-ren ZHANG Yan-sheng XIE Jian-ping QIN Wen-qing WANG Jun QIU Guan-zhou 《Journal of Central South University》 SCIE EI CAS CSCD 2020年第5期1367-1372,共6页
Bioleaching is regarded as an essential technology to treat low grade minerals,with the distinctive superiorities of lower-cost and environment-friendly compared with traditional pyrometallurgy method.However,the biol... Bioleaching is regarded as an essential technology to treat low grade minerals,with the distinctive superiorities of lower-cost and environment-friendly compared with traditional pyrometallurgy method.However,the bioleaching efficiency is unsatisfactory owing to the passivation film formed on the minerals surface.It is of particular interest to know the dissolution and passivation mechanism of sulfide minerals in the presence of microorganism.Although bioleaching can be useful in extracting metals,it is a double-edged sword.Metallurgical activities have caused serious environmental problems such as acid mine drainage(AMD).The understanding of some common sulfide minerals bioleaching processes and protection of AMD environment is reviewed in this article. 展开更多
关键词 BIOLEACHING sulfide minerals MICROORGANISM acid mine drainage
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Kinetics of acid-oxygen leaching of low-sulfur Ni-Cu matte at atmospheric pressure 被引量:4
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作者 范川林 李斌川 +1 位作者 符岩 翟秀静 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第6期1166-1170,共5页
The leaching of low-sulfur Ni-Cu matte in acid-oxygen(CuSO4-H2SO4-O2)solution at atmospheric pressure was researched.This matte was obtained from high grade Ni-Cu matte by magnetic separation,which mainly contained Ni... The leaching of low-sulfur Ni-Cu matte in acid-oxygen(CuSO4-H2SO4-O2)solution at atmospheric pressure was researched.This matte was obtained from high grade Ni-Cu matte by magnetic separation,which mainly contained Ni-Cu alloy and a small quantity of sulfides.The effects of temperature,agitation speed,oxygen flow rate,particle size,acid concentration and concentration of copper ion were studied.It is found that the matte particles are leached by shrinking core mechanism and the leaching process is electrochemically controlled.In a temperature range of 30-60℃,the surface reaction is rate-limiting step,with an apparent activation energy of 41.9 kJ/mol.But at higher temperature(70-85℃),the rate process is controlled by diffusion through the product layer,with an apparent activation energy of 7.3 kJ/mol. 展开更多
关键词 acid-oxygen leaching Ni-Cu matte Ni-Cu alloy apparent activation energy leaching kinetics
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Mobility of Arsenic and Heavy Metals in a Sandy-Loam Textured and Carbonated Soil 被引量:8
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作者 I. GARC íA M. DIEZ +2 位作者 F. MART íN M. SIMóN C. DORRONSORO 《Pedosphere》 SCIE CAS CSCD 2009年第2期166-175,共10页
The continued effect of the pyrite-tailing oxidation on the mobility of arsenic, lead, zinc, cadmium, and copper was studied in a carbonated soil under natural conditions, with the experimental plot preserved with a l... The continued effect of the pyrite-tailing oxidation on the mobility of arsenic, lead, zinc, cadmium, and copper was studied in a carbonated soil under natural conditions, with the experimental plot preserved with a layer of tailing covering the soil during three years. The experimental area is located in Southern Spain and was affected by a pyrite-mine spill. The climate in the area is typically Mediterranean, which determines the rate of soil alteration and element mobility. The intense alteration processes that occurred in the soil during three years caused important changes in its morphology and a strong degradation of the main soil properties. In this period, lead concentrated in the first 5 mm of the soil, with concentrations higher than 1500 mg kg?1, mainly associated to the neoformation of plumbojarosite. Arsenic was partially leached from the first 5 mm and mainly concentrated between 5–10 mm in the soil, with maximum values of 1239 mg kg-1; the retention of arsenates was related to the neoformation of iron hydroxysulfates (jarosite, schwertmannite) and oxyhydroxides (goethite, ferrihydrite), both with a variable degree of crystallinity. The mobility of Zn, Cd, and Cu was highly affected by pH, producing a stronger leaching in depth; their retention was related to the forms of precipitated aluminium and, in the case of Cu, also to the neoformation of hydroxysulfate. 展开更多
关键词 ARSENIC heavy metals oxidation pyrite-tailing SOIL
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